The field of this invention relates to the provision of at least one temporary deck in the open cargo space of an intermodal container. More specifically, it relates to the hanger means which extend downwardly from the ceiling to the floor of the container and from which the deck is supported.
As is known in the freight industry, that particular goods or products, for whatever purpose, can bear only so much weight in transport. For example, there are limitations on the amount of weight that the average shipping container of electronic products can bear. Additionally, certain products, such as automobiles, by virtue of the fact of their size and design and the fact they are not shipped in containers, are not stackable directly one on another. At the same time the trend in the industry is that the size of intermodal cargo containers are growing larger and larger. Additionally, the increase in size of semi-truck trailers is following a change in the legal maximum cargo weight. Thus, the cargo space available and weight limitations have increased faster than the load-carrying capacity of the packaging boxes of the products being shipped. As a result, it may be possible to only fill one-half or even one-third of an intermodal container without running the risk of crushing or in some way damaging the product on the bottom of the stack.
In order to solve this stacking problem, it is a known industry practice to divide up the open cargo area of an intermodal container with various decks. Thus, all of the available cargo space can be effectively used without the risk of crushing any of the product.
For the most part such systems incorporate temporary decking devices with which few problems have been encountered. However, in the area of the hanger means, which support the decking devices, certain difficulties have been experienced. As is apparent, these systems are by their very nature temporary and thus the hanger means must be installed quickly and efficiently with little or no modification to the existing intermodal container.
Because the top rail is a common element on various types of intermodal cargo containers, deck hangers have in some way made use of them in the support of the deck. In the normal situation, the top rail is an integral part of the cargo container and generally extends the length of the container on both sides thereof a few inches from the top. It can take various shapes as well as have different attachment to the container itself, but a common feature is a ledge or projection which extends out into the cargo area several inches. The deck hanger thus incorporates some means for cooperating with the top rail while the portion that extends down the side wall of the cargo container includes other means that facilitate the carrying of the deck. In practice, such deck hangers will be positioned every one foot or so depending on the load to be carried, the length of both major walls of the cargo container. Cross members are then extended from one wall to the other and the flooring placed thereon.
As stated, however, this is not without difficulty. For example, whatever the gripping means which is provided to cooperate with the top rail, it must take into consideration manufacturing variances with respect to the thickness of the top rail and with respect to tolerance stack-up of the hanger itself. The hanger means must be such that it can be installed by a single individual worker generally while standing on the floor of the cargo container. Additionally, the strap portion which hangs down from the gripping means must be substantially coextensive with the wall. This problem manifests itself in the fact that the deck or support bars are of a fixed length and once inserted in a strap portion on one wall, will extend across the cargo area to mate with the strap portion on the other wall. Thus, if the strap portions, by their design or construction, tend to extend or curve away from the wall, they will tend to define a distance therebetween which may be several inches less than the length of the bar. Thus, the installer must force them into a position whereby they are coextensive with the wall in order to effect engagement. As is apparent, engagement will be difficult but disengagement will be even more difficult since the installer will not only have to effect disengagement but work against the spring action of the two strap portions.
It is, therefore, a principle object of this invention to provide a simple, durable and relatively inexpensive hanger which allows quick attachment and removal. Another object of this invention is to provide a hanger which will increase its holding action on the top rail as the weight is increased thereon. But another object of this invention is to provide a hanger which, by its construction, will remain coextensive with the adjacent wall whether in the loaded or unloaded state. Still another object of this invention is to provide a hanger which transfers the forces being exerted thereon not only to the top rail but to the side walls of the cargo container as well.